Method of deodorizing, pasteurizing, and concentrating fluids



June 1935- H. L. MURRAY 2,003,454

METHOD 'OF DEORDORIZING, PASTEURIZING, AND CONCENTRATING FLUIDS Original Filed June 14, 1929 Y 2a o V /9 v I74 59 I w 79 Patented June 4, 1935 METHOD OF DEODORIZING, PASTEURIZINGi AND CONCENTRATING FLUIDS Henry Lamont Murray, Auckland, New Zealand,

aasignor to The Te Aroha Dairy Company Limited, Te Aroha, New Zealand Application June 14, 1929, Serial No. 870,980.

Renewed October 12, 1932.

June 21, 1928 In New Zcaland 3 Claims. 99-11) In the art of deodorizing fluids of objectionable volatile odoriferous flavours it is known to introduce the hot fluid to be deodorized into a ver-v tically disposed container (which may be steam jacketed) under a desired degree of vacuum when it is subjected to a treatment causing intense ebullition, the volatile vapours being carriedofl by the vacuum and the liquid continuously discharged from the container free from such objectionable odours.

While such'apparatus'has been found eflicient in practice for the purposes of pasteurizing, deodorizing and concentrating the fluid or liquid to be treated, there are drawbacks of which the more important may be stated as expense in construction, the necessity for more or less constant attention to see that the apparatus does not become too full of fluid, and the possibility of short-circuiting of the fluid through the machine-that is to say, a portion of the fluid may pass right through the machine without such period of treatment as is necessary to completely deodorize same.

In another arrangement it has been suggested to introduce the fluid to be deodorized into a steam jacketed vertically disposed vacuum container in a cold condition and pasteurize and deodorize the fluid by a batch process. Such a process however is inapplicable to continuous treatment of the fluid.

Now according to the present invention a method of deodorizing or pasteurizing or concentrating fluids has been devised which eliminates or minimizes the defects hereinbefore mentioned and, furthermore, the possibility of boiling over is, owing to the tremendous centrifugal force involved, practically negligible. According hereto the fluid is treated in a horizontally or substantially horizontally disposed steam jacketed vacuum container. the fluid being introduced through suitable control mechanism at the end of the container farthest from the outlet. In the case of fluids containing what I term refractory odoriferous flavours or in those cases in which the fluid is to be introduced cold it may be desirable to subject the incoming fluid to the action of saturated steam under high pressure. The steam impinging against the fluid at high pressure results in a very considerable degree of concussion occurring within the liquid, and this initial concussion in conjunction with the great expansion of steam due to the vacuum breaks the liquid into particles and causes at least partial atomization thereof on entry into the container. I Simultaneously the particles are subjected to the intense washing efl'ect of the wet steam, all assisting to cleanse the particles from the odoriferous oils which are so closely asso-- ciated therewith, and then vapourizing and/or dissolving the odorous substances within the oils. The above is propounded as a result of practical tests and experience as the theory of action of the steam. When saturated steam is used there is found-to be in practice little or no increase in the visible temperature of the fluid presumably due to the degree of vacuum within the container. It will be understood therefore that in treating such delicate fluids as cream, the bodies of which are injured at a high temperature it is essential to use saturated steam, which also provides the washing effect so desirable in assisting the process. In those cases, however, wherein the 'use of the superheated steam will not injuriously affect the liquid superheated steam may be employed.

The fluid whether subjected to such "saturated steam treatment or otherwise according to the circumstances of the case is then subjected to the influence of sweeps which by centrifugal force cause the fluid to form a wall of a thickness varying according to the position, which is preterably adjustable, of the discharge outlet of the container which is so arranged and disposed that after the wall attains a desired thickness the surplus liquid overflows through the discharge orifice to be disposed of with the assistance of a pump or other desired and suitable means.

It will be seen that, according to the herein described method, the liquid traverses the whole length of the container and is subjected to the process for the length of time requisite to eflect this passage.

The invention consists in these features and in the features and arrangements and combinations of parts hereinafter described and more particularly pointed out in the claims.

' Referring to the accompanying drawing, wherein an embodiment of the invention is illustrated,

Fig. 1 is a side elevation partly in section of the apparatus showing the inlet and outlet connections.

Fig. 2 is an elevation of the opposite side of the apparatus partly in section. i

Fig. 3 is a top plan view showing the container in section.

In one form there is provided a horizontal container l substantially cylindrical in shape peripherally surrounded by a steam jacket 2, the drum I having a flxed end 3 and a removable end 4 substantially concave in shape and being suitably mounted on a base plate 5. Fitted centrally in the fixed end 3 there is a gland 6 through which passes the sweep shaft'1 revolvably mounted in two pedestal bearings 8 and 9 fastened to the base plate 5, the said shaft 1 being provided with fast and loose pulleys III and II and at its outer end a gear wheel I2.

On the portion of shaft I projecting into container I there are mounted on a centralboss I3 the sweeps I4, preferably three in number, which pass tangentially from the said boss I3 towards the walls of container I and to a predetermined distance therefrom which varies from inch upwards, the said sweeps I4 being inclined in direction opposite to that of rotation. The sweeps do not actually contact the wall, but allow for the continuous passage or slipping of the liquid. This further assists positive contact of the liquid with the heating surface. The amount of clearance allowed is determined by the viscosity and density of the liquid commonly handled. Mounted on base plate 5 there is a centrifugal pump I5 the shaft I6 of which is supported by two bearings I1 and I8, and has mounted at its outer end a pinion I9, this latter being connected for rotary drive from the shaft 1 by a silent gear chain 20 passing over the said pinion I9 and gear wheel I 2.

In a modified arrangement, the centrifugal pump I5 may have an independent drive whereby the gear I2, pinion I9 and chain 20-would be eliminated, the pump I5 being rotated by any suitable known means. The centrifugal pump I5 has the usual delivery pipe 2| and within its union 22 is fitted a check valve (not shown), the said pump I5 also having suction pipe 23 which passes along the side of the container I provided for a portion of its length with a water jacket 24 (see Figure 2) having the usual water inlet and outlet connections 25 and 26.

To the suction pipe 23 there is fitted a bypass pipe 21 (see Figure 3) controlled by suitable valve 28, this pipe 21 being connected to the bottom of container I. The suction pipe 23 after passing along the side of container turns around the end thereof, is provided with union 29 and thermometer 30 and is connected to the removable end 4 of container I, at a point inward from the periphery of said container and preferably in the vicinity of the bottom thereof. The removable end 4 is provided with a rubber gasket 3| and is fastened to the end of container I by such means as studs and handwheels 33. The end 4 has a central hole 34 provided with a flange 35 to which is fastened a goose neck pipe 36 by such means as yoke clamp 31 adapted at its inner ends 38 to pass round the back of the flange 35 and at its outer end 39 to press against a fin 40 of the said pipe 36.

The goose neck pipe 36 passes to the branch 4| of an ejector condenser 42 (which may be of the type described in the United States patent to H. L. Murray, No. 1,641,349 mounted on base plate 5.

The branch 4| of condenser 42 has a flange 43 to which the goose neck pipe 36 is fastened by a clamp 44 (similar to yoke clamp 31) pressing against fin 45. The water-supply pipe 46 controlled by a valve 41 leads to the ejector condenser 42 and is provided with a gauge 48. The ejector condenser is provided with a vacuum gauge 49, a vacuum or snifter-control valve 50, a vacuum breaking cock 50a and a drain pipe 5|.

To the side of the container I is mounted the liquid inlet mechanism 52 (which may be of the type described in said United States Murray Patent No. 1,641,349). This mechanism 52 comprises a float chamber 53 at the top of which is the supply pipe 54 with froth eradicating valve 55, fitted to removable cover 56. To the bottom of the float chamber 53, there is connected the inlet pipe 51 which passes to near the bottom of end 3 of container I, the said pipe 51 having (see Figure 3) a T 58 to which is coupled a steam pipe with valve 60. This inlet pipe 51 is provided with a seating 6| within float chamber 53 over which slides a valve 62 actuated by the lever 63 of a float 64.

To the top of the steam jacket 2 is fitted the steam inlet pipe 65 provided with a control valve 66 and a combined pressure and vacuum relief valve 61. Within the steam jacket 2 in the vicinity of the steam inlet pipe 65 there is fitted a baflle plate 68 for preventing the incoming steam from impinging directly on to the container I in that region. To the bottom of the steam jacket 2 is fitted a drain pipe 69 with steam trap 10. In operation, the valve 41 of the ejector condenser 42 is opened and this creates a vacuum in the container I by way of goose neck 36 to a degree indicated by the vacuum gauge 49 and maintained at this desired point by the relief or snifter valve 50. The sweeps I4 are thenset in motion by a belt drive from suitable source of power to the fast pulley In which causes rotation of the shaft 1 and its attached gear wheel I2, which being connected to pinion I9 of the pump shaft I6 by the gear chain 20 simultaneously transmits the said drive to the centrifugal pump I5.

The liquid to be treated is now admitted to the float chamber 53 through the supply pipe 54 past froth eradicating valve 55, this causing the float 64 to rise, moving the valve 62 on the seating 6| until the float chamber 53 is open to the inlet pipe 51 down which the fluid passes to the container I. The liquid to be treated may have been previously pasteurized or raised to a comparatively high temperature in which case it would be admitted hot to the float chamber. Where the liquid to be treated is hot and of a refractory nature, or is cold, the steam valve is opened which causes steam from supply pipe 59 to impinge against and break up the incoming fluid into particles as has been hereinbefore described. In the case of hot unrefractory liquids it is not necessary to open the steam valve 6|) but to do so generally expedites treatment. Steam is admitted to the steam jacket 2 by opening steam valve 66, steam trap 10 is adjusted to allow the escape of condensed steam, the pressure of steam in the jacket 2 being controlled by the safety valve 61 in conjunction with regulating of the valve 66. Cold water from a suitable source of supply is permitted to flow through suction pipe jacket 24 by way of inlet and outlet 25 and 26. r

The fluid passing into the container I accumulates therein due to the outlet or pump suction pipe 23 being situated inwardly from the periphery of the said container I, the sweeps I4 revolving therein at such speed as causes the fluid to form a peripheral bandaround the container I this depth of band being determined by the distance of the outlet or pumpsuction pipe 23 from the periphery of the said container I. 'When the quantity of fluid exceeds this depth the surplus passes into the suction pipe 23 and flows therethrough to the centrifugal pump. I5, being cooled on the way by the jacket 24, which increases the efficient action of the pump. The centrifugal force engendered by the" revolving sweeps I4 creates pressure within the wall of liquid and causes the expulsion of the vapours and gases.

This centrifugal force ensures the supply of cool liquid to the hot surface of the container I; the liquid becoming heated, is displaced centrip etally by the outward flow of cool liquid and an intense circulation is thereby set up within the revolving wall of fluid. This rapid liquid circulation caused by the combination of centrifugal force and application of heat, effects: a. Very rapid absorption of heat, thus giving speedy evaporation. b. Very even heating of the particles thus ensuring effective pasteurization. 0. Minimum duration of liquid contact with the heating surface, so avoiding fusion of the solids therewith and the resultant insulation of the surface and development of cooked flavours in the fluid. The

centrifugal action of the pump I5 forces the fluid out through the delivery pipe 2| past the check valve (not shown) in the union 22 thereof, this check valve preventing air from entering into the container I through the suction pipe 23 and breaking the vacuum.

The deodorization process is continuous, liquid flowing into one end of the container I by the inlet pipe 51 and out at the other end by the suction or outlet pipe 23, the delivery temperature being determined by the thermometer 30 on said pipe 23, the float 64 in chamber 53 rising and falling and preventing the vacuum of container I from becoming broken by the admission of air through inlet pipe 51. The vacuum created by the action of the ejector condenser 42 causes the hot vapors arising from the hot liquid to be drawn through the goose neck pipe 36 to the said condenser 42 wherein they are condensed and discharged along with the ejector water through the drain pipe 5|.

It being desired to stop the plant, the float 64 is allowed to settle to the bottom of the chamber 53 thus closing the slide valve 62. The steam valve 66. is closed, vacuum breaking cock 50a opened so asto break vacuum in container I and the condenser pressure water valve 41 closed. The by-pass valve 28 is then opened and this permits the fluid in container to pass through the by-pass pipe 21 to the suction pipe 23 and from thence to the pump l5 as previously described, this by-pass enabling the complete draining of the container l. The water supply to the jacket 24 of suction pipe 23 is then shut off and rotation of the sweeps l4 and pump l5 also stopped.

To gain access to container l for cleaning purposes the goose neck pipe 36 is removed by slipping th yoke clamps 31 and 44 therefrom and suction pipe 23 is disconnected at its union 29. By slackening off the handwheels 33 the end 4 can be removed, thus leaving an open end to the container I, and by removing the setscrew shown. the sweeps l4 and boss II can be withdrawn from shaft 1, also for cleaning purposes.

I claim: I

1. The method of deodorizing liquids by evaporating volatile essences and entraining non-volatile odorous substances, 'said method consisting in introducing heated liquid into a container. injecting steam into previously heated liquid flowing to the container, supplying heat to the liquid in said container to maintain the same, at

boiling temperature, subjecting said liquid to centrifugal force to produce a revolvingwall of liquid within the container and effect radial molecular circulation within said wall of liquid, thereby expelling vapors and fixed gases from the liquid, condensing said vapors and exhausting said fixed gases thereby maintaining vacuum in said container, withdrawing liquid from said container and preventing increase in vacuum above a predetermined figure, thereby controlling the boiling point of the liquid.

2. The method of deodorizing liquid by evaporating volatile essences and entraining non-volatile odorous substances, said method consisting in continuously introducing heated liquid into a container, injecting steam into the previouslyheated liquid stream flowing to the container, supplying heat to said container to maintain the liquid in the container at boiling temperatura applying centrifugal force to said liquid to produce a revolving wall of liquid and effect radial molecular circulation within said wall of liquid, thereby continuously expelling vapors and fixed gases from the liquid, continuously condensing said vapors and exhausting fixed gases thereby maintaining high vacuum in said container, continuously withdrawing liquid from said container and preventing increase in vacuum above a predetermined value, thereby controlling the boiling point of the liquid.

3. The method of deodorizing cream, milk or other similar liquid by evaporating volatile essences and entraining non-volatile odorous substances, said method consisting in continuously introducing heated liquid into a container, injecting steam into the previously heated liquid prior to its introduction into the container, utilizing centrifugal force to produce a revolving wall of liquid within said container, thereby continuously expelling vapors and fixed gases from the liquid, continuously condensing said vapors and exhausting said fixed gases thereby maintaining high vacuum in said container, contin -uously withdrawing liquid from said container 

